NumberingData
Verified Nov 1, 2026 · Source: NANPA CO Code Assignment Records

ST JAMES prefixes in area code 631

NANPA records 6 assigned NXX blocks to rate center ST JAMES in area code 631, 0.8% of the 782 blocks assigned in the code. A rate center is the billing geography a block is allocated to – NANPA truncates the name to ten characters, so read it as a NANPA label rather than a town. 4 holders hold those blocks, the largest being MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NY (2), VERIZON NEW YORK, INC. (2), CSC VOICE, LLC (1). The earliest assignment on record here is 2013-04-09 and the most recent 2013-04-09. 6 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots. The same rate center name also appears in area codes 231, 235, 507, 573 – overlay codes cover the same geography, so a rate center is served by all of them.

6 assigned blocks – 0.8% of 631
4 holders of record
6 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
631-250 CSC VOICE, LLC 2013-04-09 yes yes
631-551 Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NY – yes yes
631-584 Verizon VERIZON NEW YORK, INC. – yes yes
631-621 Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NY – yes yes
631-686 Altice CABLEVISION LIGHTPATH, INC. - NY – yes yes
631-862 Verizon VERIZON NEW YORK, INC. – yes yes

The holder is who received the block from the numbering administrator. It is not necessarily the carrier serving a given number: numbers move with their owners, and a pooled block is shared.

Who holds the blocks

HolderBrandBlocksShare here
MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NY Verizon 2 33.3%
VERIZON NEW YORK, INC. Verizon 2 33.3%
CSC VOICE, LLC – 1 16.7%
CABLEVISION LIGHTPATH, INC. - NY Altice 1 16.7%

Same rate center in other codes

Overlay codes cover the same geography, so one rate center is served by all of them.

Frequently asked

Which prefixes belong to ST JAMES in area code 631?

6 blocks: 250, 551, 584, 621, 686, 862. The table above gives the holder of each.

Which carriers have numbers in ST JAMES?

MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NY (2 blocks), VERIZON NEW YORK, INC. (2 blocks), CSC VOICE, LLC (1 block), CABLEVISION LIGHTPATH, INC. - NY (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is ST JAMES a city?

It is a rate center – the unit NANPA allocates number blocks to. Its name is abbreviated to ten characters and is not necessarily a settlement: we print it as recorded rather than guess at the full name.

Other rate centers in 631

All 782 prefixes in 631